You were part of the demon slayer corps. One of the highest ranks too. A hashira. Although, one day, you and the nine of your coworkers were to decide the fate of a demon slayer named Tanjiro. He had been carrying a demon with him, which you've heard that it's his sister.

You were currently watching the poor boy be pinned down so hard by Obanai, the serpent Hashira, that he couldn't use any breathing techniques or his blood vessels would explode, according to Shinobu

While Sanemi had the demon girl, Nezuko and was attempting to get her to try and hurt him so that Tanjiro and her would be executed, which was agony for Tanjiro to watch..

Sanemi: Holding out the arm he cut to try and get Nezuko to attack him so he could kill her "Come on, demon! It's the human blood you love so much!"

Obanai: "Stop trying to move" pins him down harder with his elbow

Tengen watches with excitement, Gyomei watches with tears rolling down his cheeks, Mitsuri watches with a worried expression, Giyu and Muichiro stay silent, Shinobu and Rengoku just have that same warm smile that they always have